• Our booking engine at tickets.railforums.co.uk (powered by TrainSplit) helps support the running of the forum with every ticket purchase! Find out more and ask any questions/give us feedback in this thread!

Freight over 3rd rail

Status
Not open for further replies.

pompeyfan

Established Member
Joined
24 Jan 2012
Messages
4,181
After reading the post regarding class 69s potentially releasing some class 73s in the Kent area, it had me wondering what is the longest freight journey over 3rd rail? I’m aware there may be some last mile diesel involved in yards etc but surely more freight could be 73 hauled without switching locos mid journey? My guess would be the Southampton Gypsum train?
 
Sponsor Post - registered members do not see these adverts; click here to register, or click here to log in
R

RailUK Forums

zwk500

Veteran Member
Joined
20 Jan 2020
Messages
13,223
Location
Bristol
After reading the post regarding class 69s potentially releasing some class 73s in the Kent area, it had me wondering what is the longest freight journey over 3rd rail? I’m aware there may be some last mile diesel involved in yards etc but surely more freight could be 73 hauled without switching locos mid journey? My guess would be the Southampton Gypsum train?
To my knowledge all freight in the 3rd rail area is currently hauled by diesel. 73s run the seasonal departmental trains (and some stock moves). I may well be corrected by later posters.
 

Deepgreen

Established Member
Joined
12 Jun 2013
Messages
6,340
Location
Betchworth, Surrey
I think the requirement for double-heading (at least) with 73s on today's freight weights may be a limiting factor. Even with a combined 3,200hp on electric, they are Bo-Bos so don't have the tractive effort of Co-Co locos designed for freight. Then there is the issue of the sections which may need diesel - taking it down to 1,200hp.
 

Fincra5

Established Member
Joined
6 Jun 2009
Messages
2,486
GBRf have run 92s over the Juice, not too long ago! HS1 has obvs taken most 92's off Kent's Juice...

There are deffo routes where something like a Bi-Mode would be useful! Newhaven to Purley for example... But then Power Supply can become a limiting factor.
 

43096

On Moderation
Joined
23 Nov 2015
Messages
15,162
I think the requirement for double-heading (at least) with 73s on today's freight weights may be a limiting factor. Even with a combined 3,200hp on electric, they are Bo-Bos so don't have the tractive effort of Co-Co locos designed for freight. Then there is the issue of the sections which may need diesel - taking it down to 1,200hp.
Unless they use a 73/9, which have similar outputs on electric and diesel.
 

zwk500

Veteran Member
Joined
20 Jan 2020
Messages
13,223
Location
Bristol
GBRf have run 92s over the Juice, not too long ago! HS1 has obvs taken most 92's off Kent's Juice...

There are deffo routes where something like a Bi-Mode would be useful! Newhaven to Purley for example... But then Power Supply can become a limiting factor.
Unless they use a 73/9, which have similar outputs on electric and diesel.
Surely a even a 73/9 (or a pair) would struggle to get a loaded aggregate train from Mitre Bridge to Acton Yard on it's diesel power alone?
 

43096

On Moderation
Joined
23 Nov 2015
Messages
15,162
Surely a even a 73/9 (or a pair) would struggle to get a loaded aggregate train from Mitre Bridge to Acton Yard on it's diesel power alone?
What hauls them currently? A 66?
 

hwl

Established Member
Joined
5 Feb 2012
Messages
7,354
After reading the post regarding class 69s potentially releasing some class 73s in the Kent area, it had me wondering what is the longest freight journey over 3rd rail? I’m aware there may be some last mile diesel involved in yards etc but surely more freight could be 73 hauled without switching locos mid journey? My guess would be the Southampton Gypsum train?
Much more likely to be releasing 66s on heavier engineering trains or infrastructure supply (bulk ballast) trains in/out of Tonbridge Yard to allow them to do potential HS2 work instead...
Not much change likely in 73s use.
 

43096

On Moderation
Joined
23 Nov 2015
Messages
15,162
Yes. What rating are 73/9s on diesel, I thought they're c.1,500hp but quite light on their axles?
Correct on the rating, so a pair would have a similar output to a 66, but over 8 axles rather than 6. Given the modern control systems on the 73/9s (do they have SEPEX - can’t remember) I would think a pair could handle it.
 

pompeyfan

Established Member
Joined
24 Jan 2012
Messages
4,181
Is there many/any freight flows that could be 3rd rail powered with a last mile system?
 

Deepgreen

Established Member
Joined
12 Jun 2013
Messages
6,340
Location
Betchworth, Surrey
Correct on the rating, so a pair would have a similar output to a 66, but over 8 axles rather than 6. Given the modern control systems on the 73/9s (do they have SEPEX - can’t remember) I would think a pair could handle it.
You may be right, but a 66 has a TE of 92,000lb whereas a pair of 73s has around 75,000lb. They could give it a go but might struggle. The extra two axles may help. I think, though, that the 73s are just regarded as lighter train-weight units. There is a minimal strategic push to have freight electrically-hauled anyway.
 

popeter45

Member
Joined
7 Dec 2019
Messages
1,105
Location
london
isnt one of the big issue the fact that most third rail areas not have the power capacity for frieght?
even a 12 car EMU must draw draw far less power than a electric loco struggling with a aggregate load would?
 

Western Sunset

Established Member
Joined
23 Dec 2014
Messages
2,493
Location
Wimborne, Dorset
After reading the post regarding class 69s potentially releasing some class 73s in the Kent area, it had me wondering what is the longest freight journey over 3rd rail? I’m aware there may be some last mile diesel involved in yards etc but surely more freight could be 73 hauled without switching locos mid journey? My guess would be the Southampton Gypsum train?
I think you're right. 139 miles over the juice with a Cl.66. Just the first bit in the sidings at Mountfield and the last 1/2 mile into Soton W Docks from Millbrook lack the 3rd rail.
 

swt_passenger

Veteran Member
Joined
7 Apr 2010
Messages
31,263
The fairly limited number of 73s I have seen on freight or infrastructure duties in the Hampshire area have almost all been operating on diesel. I suspect in places further east where they’re a bit more common they’re being chosen for their RA number compared to a 66, rather than the benefits of electric power...
 

Domeyhead

Member
Joined
10 Nov 2009
Messages
386
Location
The South
There's a good piece by Ian Walmsley in the current Modern Railways. Not about Class 73s or third rail but the issue of electric freight haulage, timings and multiple modes. The upcoming class 93 is already tri mode - if it became a quad mode it would gobble up all southern freight at a canter.
 

HSTEd

Veteran Member
Joined
14 Jul 2011
Messages
16,632
even a 12 car EMU must draw draw far less power than a electric loco struggling with a aggregate load would?

Not really.
If performance comparable to diesel is acceptable, a Class 66 has only 2240kW at rail.
That makes it somewhere between eight and nine cars of Class 377 formation.
 

Grumbler

Member
Joined
27 Mar 2015
Messages
508
isnt one of the big issue the fact that most third rail areas not have the power capacity for frieght?
even a 12 car EMU must draw draw far less power than a electric loco struggling with a aggregate load would?
This is probably a bonkers idea, but would it be feasible to boost the power at selected places by installing a second third rail on the other side? Or would this fry the running rails?
 

DustyBin

Established Member
Joined
20 Sep 2020
Messages
3,613
Location
First Class
This is probably a bonkers idea, but would it be feasible to boost the power at selected places by installing a second third rail on the other side? Or would this fry the running rails?

It’s the substations etc. that are the problem, not the 3rd rail itself.
 

Carlisle

Established Member
Joined
26 Aug 2012
Messages
4,122
Not a lot of spare capacity in the GBRf 73/9 fleet beyond their contracted infrastructure work.
It’s a shame the industry has only opted to refurbish 50-60 year old traction rather than meet the challenge of introducing a new fleet of 3rd rail capable locos
 

pompeyfan

Established Member
Joined
24 Jan 2012
Messages
4,181
Is there actually that many flows though? The gypsum was identified as the longest, followed by the Acton - Newhaven aggregates but I can’t think of much else.
 

D365

Veteran Member
Joined
29 Jun 2012
Messages
11,396
It’s a shame the industry has only opted to refurbish 50-60 year old traction rather than meet the challenge of introducing a new fleet of 3rd rail capable locos
What challenge is that? What would be the point when 750V is clearly inadequate for anything other than metro operations.
 

CW2

Established Member
Joined
7 May 2020
Messages
1,922
Location
Crewe
What challenge is that? What would be the point when 750V is clearly inadequate for anything other than metro operations.
750V DC was entirely adequate for freights to / from the Channel Tunnel, hauled by class 92s.
 

southern442

Established Member
Joined
20 May 2013
Messages
2,186
Location
Surrey
What challenge is that? What would be the point when 750V is clearly inadequate for anything other than metro operations.
I wouldn't necessarily call a lot of routes in 3rd rail land metro operations (although plenty in London are)
 
Status
Not open for further replies.

Top